Scientific Investigations and Variables

A student is planning an experiment to find out how the height from which he drops a ball affects how high the ball bounces. The dependent (outcome) variable is the _____.

• Diameter of the ball

• Force acting on the ball

• Height that the ball bounces

• Height from which the ball is dropped

A student is planning an experiment to find out how the height from which he drops a ball affects how high the ball bounces. What is a constant (controlled variable)?

• The ball used

• The height the ball bounces

• Height of the ball being dropped

The variable that is being measured and recorded in the data table.

• independent variable

• dependent variable

• control variable

Scientific Question:  Does playing video games improve reaction time?
What is the independent variable?

• playing video games
• reaction time
• type of video game

How many independent variables can be tested in a controlled experiment?

• one
• two
• three
• as many as possible

A bug repellant is sprayed on one arm while the other arm is not sprayed. The number of bug bites is recorded after 2 hours. The DEPENDENT variable is -

• The size of the arm

• bug repellant or not

• the different types of bugs

• the number of bug bites

Why do we want to test one variable at a time?

• Because it is hard to setup a data table with more

• To know what is actually causing the changes

• It is what has always been done

• No one really knows

Identifying the independent and dependent variables in an experiment will help you better interpret and convey results. What is the difference between the independent and dependent variables in an experiment?

• The independent variable is always a number, and the dependent variable is never a number.

• The independent variable is what you set up and change, and the dependent variable is what you measure and record data about.

• The dependent variable is what the investigator controls, and the independent variable is what happens as a result of this.

Mr. McNeice wanted to know if different types of music affected people's heart rates, so he played different music and checked their pulses.  What is the dependent variable?

• type of music
• heart rate
• how long they listend to music
• Mr. McNeice

This is the outcome of the experiment. We get data and results from this.

• Independent Variable
• Dependent Variable
• Control
• Constant

Tags

NGSS.MS-LS2-1